The use of servers as devices within communications networks is well known in the art. A server is equipment that makes available file, database, printing, facsimile, communications or other services to client terminals/stations with access to the network the server serves. When the server permits client/terminal station access to external communications network it is sometimes known as a gateway Servers are available in different sizes, shapes and varieties. Servers may be distributed throughout a network or they may be concentrated in centralized data centers.
Advances in centralized data processing centers have resulted in smaller form factors for server devices and an increase in the density of processing units, thereby reducing space requirements for computing infrastructure. One common form factor has been termed in the art a “blade server,” comprising a device built for vertically inserting into a chassis that can house multiple devices that share power and other connections over a common backplane, i.e., a blade center. Slim, hot swappable blade servers (also referred to herein as “blades”) fit in a single chassis like books in a bookshelf—and each is an independent server, with its own processors, memory, storage, network controllers, operating system and applications. The blade server slides into a bay in the chassis and plugs into a mid- or backplane, sharing power, fans, floppy drives, switches, and ports with other blade servers. The benefits of the blade approach will be readily apparent to anyone tasked with running down hundreds of cables strung through racks just to add and remove servers. With switches and power units shared, precious space is freed up—and blade servers enable higher density with far greater ease. With a large number of high-performance server blades in a single chassis, blade technology achieves high levels of density.
Even though power consumption and device complexity per unit of processing power may actually decrease with a blade center, since the physical density of the computing devices has increased, the demands on power consumption for processing power and cooling have also intensified as overall computing power has increased. A blade center chassis has resources such as power and cooling that are shared by multiple components in the enclosure. A management module is present in each chassis which is responsible for managing all components within a chassis and the relationship between them. Each blade is allocated a fixed amount of power or cooling capacity. If any blade exceeds its allocation, it can force the entire chassis to exceed threshold values, which can, in turn, force the common power supply to shut down, causing other blades to be turned off. Another risk is that any blade exceeding its allocation can cause other blades to shut down due to temperatures exceeding their critical thresholds.
Probably, one of the most pressing problems associated with servers is manageability and particularly manageability as applied to chassis mounted servers. One aspect of manageability within this type of server relates to allocating power resources, which has been solved by system architecture in past configurations. Service processors on blades are required to ask the management module for permission to power on and to shut down when requested by the management module. In such a configuration, the blade server continues to maintain control over its own power consumption. In past system architectures, this feature has been preserved so that blade servers can continue to operate in an environment where the management module is not present. While past architectures have thusly addressed the majority of cases, they have not addressed the case where a blade server malfunctions, i.e., does not properly respond to the directives of the management module. Therefore, past blade center system architectures have been susceptible to the malfunction of a single blade that does not follow the required protocol for power management, for example, by choosing to power on in inappropriate situations, thereby jeopardizing the operation of other blades in the chassis.
In view of the above problems a more reliable system and method is needed to enforce power control in a blade center chassis to prevent overloading of power and cooling resources due to a non-compliant, malfunctioning blade server.